Efficient mining method for electric shovel on slope road

Abstract

The application discloses a kind of electric shovel slope road efficient mining operation method, comprising the following steps: first, determine the standard of slope road;Second, reasonable planning blast area;Third, mining method and mine car turning mode;Fourth, the operation mode of night slope road.The purpose of the present application is to provide a kind of electric shovel slope road efficient mining operation method, which not only reduces the waiting time of mine car, improves the efficiency of electric shovel operation, but also reduces the labor intensity of driver, reduces the efficient mining operation method of fatigue operation.

Description

Technical Field

[0001] This invention relates to the field of rapid trenching operations using electric shovels in open-pit mines, and more particularly to a method for efficient mining operations on inclined roads using electric shovels. Background Technology

[0002] The current working environment features narrow roads, posing a significant challenge to constructing ramps. If the design time is too long, it impacts the mining area's production schedule. Previously, constructing a single ramp took over 40 shifts. The ramp construction is primarily based on a decreasing calculation: for every 17.5 meters the excavator advances, it simultaneously digs downwards by 14 meters. This means that for every 17.5 meters forward, it digs downwards by 1.4 meters. Because the WK-10B electric shovel's digging angle, after maintaining a 1.5-meter horizontal digging position, moves in an upward arc, each forward digging action requires digging downwards a certain distance to ensure the 175-meter ramp reaches the next horizontal level. After all the material within the maximum digging radius (18.7 meters) of the shovel's position is cleared, the moving equipment advances. This process is repeated, using a bucket excavation method to excavate the material. After each forward movement, once the equipment has come to a complete stop, ensure the driver's cab and both side retaining walls are level. Observe the angle gauge on the equipment; the scale should be between 6 and 8 degrees. If it is below 6 degrees, dig downwards immediately. If it is above 8 degrees, padding is required for the area being excavated.

[0003] This construction method is time-consuming and the slope cannot be controlled. Multiple adjustments to the length and slope of the ramp are required to achieve the required standard. The driver's operation is not ideal, making this method impractical. Mining based on an angle gauge of 6-8 degrees revealed a final road surface slope greater than 8%, and the actual road surface length did not reach 175 meters. The large vertical drop of the ramp, coupled with the heavy load on the ore trucks continuously moving uphill, resulted in significant dynamic loads, increased resistance, and prevented the vehicles from reaching economical operating speeds. This led to excessive fuel consumption, increased transportation costs, and safety hazards. Furthermore, it caused numerous rework attempts, delays in project completion, and other problems, directly impacting the economic efficiency of mining and increasing operating costs.

[0004] Based on the practical experience of constructing ramp roads in recent years, and in order to complete the construction of ramp roads better and faster as required by the operations department, the project must be completed in one go to reduce rework, lower transportation costs, and ensure transportation safety. The mining section, through its past road construction experience, has developed a set of fast, effective, and high-quality mining methods using the WK-10B electric shovel. Summary of the Invention

[0005] The purpose of this invention is to provide an efficient mining operation method using electric shovels on inclined ramps. This method not only reduces the waiting time of ore trucks and improves the efficiency of electric shovel operations, but also reduces the labor intensity of drivers and reduces fatigue. Transportation costs account for approximately 50% of the total mining cost. With the expansion of the Bayan Obo iron ore mine's production scale, the haulage distance in the tunnels is becoming increasingly longer. Constructing rationally designed inclined ramps is an effective way to reduce the haulage distance of ore trucks, thereby reducing fuel costs and tire consumption. Constructing inclined ramps is crucial for cost reduction and efficiency improvement. Due to its small operating radius, flexible operation, and mature travel mechanism, it can be used in conjunction with 172 and 260 type ore trucks to more effectively excavate on inclined ramps.

[0006] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0007] This invention discloses an efficient method for mining on inclined roads using electric shovels, comprising the following steps:

[0008] The first step is to determine the standards for the ramp: Before starting ramp construction, the span and distance between the upper and lower ends of the ramp to be constructed must be observed to determine the required slope. The basic elements of a ramp include: ramp width, ramp depth, longitudinal slope, and ramp length. These are calculated based on the current climbing ability and safety distance of iron ore transport vehicles.

[0009] The second step is to rationally plan the blasting area (refer to blasting operation standards):

[0010] The completion of a sloping road often involves many factors, and the quality of the explosive charge is one of the main factors affecting the excavation progress. To ensure blasting quality, blasting personnel must strictly follow the requirements, including pre-loading explosives, especially in areas with high moisture content, allowing sufficient settling time to ensure the explosives' effectiveness. The amount of explosive in each blast hole should be appropriately increased, and shock-absorbing blasting should be used near the final slope. If the explosive charge particles are too large, it will increase the excavation resistance of the electric shovel, severely affecting the excavation progress. The parameters of the explosive charge are also subject to certain requirements, such as a minimum length of 175 meters and a minimum width of 40 meters. The entrance to the slope is the edge of the resistance line; if any collapse occurs, it must be filled in promptly. Before construction, the blasting area must be carefully inspected to confirm the absence of large chunks and frozen soil on the top; if any are found, immediate action must be taken.

[0011] The third step involves mining methods and the turning mechanism of ore transport vehicles:

[0012] A reasonable mining method and the correct operation of equipment by the operator are the keys to the excavation progress, and the design of the ramp entrance is critical. First, conditions shall be created for the haulage of ore trucks. Drive the equipment to the center of the road to expand the reversing area for ore trucks, and the excavation scope shall not exceed the warning points placed by the construction supervisor. If there is not sufficient material for loading, the excavator shall be used to pile up the material at the reversing position. After the site is fully expanded, the equipment shall retreat to the side where the cables are placed to carry out loading operations.

[0013] Step 4: Operation method for nighttime work on the ramp:

[0014] From the safety perspective of ramp operations, there are potential safety hazards for operators during measurement at night, so it is required that the ramp be excavated by flat mining at night, and the gradient is controlled by daytime operators. This requires that when mining during the daytime, for every 10 meters of forward mining, the operator shall measure the depth of the ramp, that is, the vertical distance from the upper level to the lowest mined point increases by 0.8 meters. During the mining process, the operator shall cooperate with the inclinometer on the equipment to control the excavation depth, and the inclinometer of the equipment shall always be controlled between 4 and 5 degrees. The actual depth measurement and the angle control of the equipment's inclinometer complement each other.

[0015] Further, in the first step, the standard calculation of the ramp: (1) Ramp standard: the ramp has a length of 175M, a width of 26M, and a gradient of 8%. (2) Road surface flatness: there shall be no pits or bumps with a diameter of 50CM and a height / depth of more than 30CM, and no mud pumping phenomenon. (3) Turning setting: the cross slope of the turning area is maintained at 1.5%-2%. The inner side must have a road surface widening of 2.5M-3M, the superelevation is determined according to the road width and cross slope, and the inner side of the vehicle traveling on the road surface in the turning area has a driving sight distance of no less than 50M. (4) Safety retaining wall: all safety retaining walls are designed according to the tire diameter requirements of ore haulage vehicles, that is, the cross section is an isosceles trapezoid, with a base width of not less than 5M, a top width of 1M, and a retaining wall height of 1.5M. Where: h — bench height, 14m, i — gradient, from Tan<i=8%, it is derived that L=h / i=14 / 0.08=175M, and the horizontal distance is 175M. Note: (1) According to the Pythagorean theorem: a 2 +b 2 =c 2 It is derived that the length of the ramp is 175.56 meters (the difference from the ramp length is negligible). (2) Conversion between gradient and angle: (Tan<i=14m / 175m) = 4 degrees and 34 minutes (8% gradient converted to an angle is 4 degrees and 34 minutes).

[0016] Furthermore, in the second step, the entrance to the ramp is at the edge of the resistance line; if there is any collapse, it needs to be filled in promptly. No other equipment should be operating in the same direction below the excavation area to prevent large blocks from suddenly sliding down and causing injury to equipment and personnel below. Construction workers should mark the width and length of the road to be constructed on the blast pile as a warning.

[0017] Furthermore, in the second step, the forward thrust of the blasted material source must be longer and wider than the ramp. If the remaining material source is also excavated using road-building equipment, it will inevitably affect the project progress. To expedite the project, another excavator is needed to work on the next level. To control the length and width of the ramp, technicians need to precisely place the excavation points, which are particularly important. These points should be placed 175 meters long and 40 meters wide above the material source. The excavator working on the next level will excavate the excess material according to the placed warning signs. It is important to note that the upper and lower equipment must cooperate and operate in opposite directions when working simultaneously. When the two machines have excavated to an intersection of 5-8 meters, the lower equipment must promptly move to a safe location, constantly observing the warning signs, and avoiding over-excavation to prevent landslides.

[0018] Furthermore, in the third step, the ore truck reverses using different turning methods at the initial and middle / late stages of the slope. Based on the width of the slope (26 meters) and the turning radius of the 172-type ore truck, two turning methods are calculated to meet the requirements of the ore truck: turning around outside the slope and turning around and testing inside the slope.

[0019] Furthermore, in the fourth step, when the slope is 0.5 meters away from the next horizontal plane, the driver judges by the top of the 10-foot shovel's top wheel approaching the previous horizontal plane (the top wheel is 13.5 meters away from the ground). The shovel's digging depth needs to be adjusted, starting from 5 degrees on the angle gauge and gradually adjusting towards 0 degrees.

[0020] Compared with the prior art, the beneficial technical effects of the present invention are as follows:

[0021] Safety benefits after application: On the one hand, it can improve the operating efficiency of electric shovels, while ensuring the operation of electric shovels and ore trucks, reducing the time wasted when electric shovels turn at large angles, improving flatness, and reducing waves, tire punctures, and abnormal wear of electric shovel tracks; on the other hand, it can also ensure the safety of ore trucks operating at night, effectively preventing ore trucks from exceeding the width of the road surface, thereby preventing tire punctures and other safety problems.

[0022] The rapid construction of ramp roads has improved the transportation efficiency of ore trucks, reduced costs, and decreased the occurrence of accidents, laying the foundation for optimal economic benefits and safe production in the mine. The main mining operation at the 1402-1388 level north side, based on previous experience with ramp road construction, has gradually developed a set of mining methods suitable for the use of WK-10B electric shovels and hydraulic shovels in conjunction with ramp road construction. All economic and technical indicators are superior to previous attempts. The progress and difficulty of this ramp road construction are significantly improved compared to previous projects, and the slope and length of the ramp meet standards. Considering the operating efficiency of the electric shovel, the current construction method allows for completion 20 shifts ahead of schedule compared to the previous road construction period, and the ramp road can be put into production 10 days earlier, shortening the preparation cycle for the new level. Completing the project 10 days earlier allows for an additional 10 days (20 shifts) of production. At a shift efficiency of 7890 tons / shift, this translates to an additional 7890 × 20 = 157800 tons of ore. From a transportation cost perspective, the main costs are concentrated in tires and fuel consumption. These two factors combined account for approximately 60% of the total cost of open-pit mining. The levels of these two items directly impact the overall production cost of the open-pit mine and its economic benefits. Standard sloping roads can reduce fuel consumption of ore trucks and ensure their safe operation. From an auxiliary equipment perspective, eliminating the previous need for hauling pre-loaded materials significantly reduces the operating costs of auxiliary equipment.

[0023] The construction of ramp roads is a crucial component of the entire open-pit mine production system. The level of standardized construction quality of ramp roads directly impacts the mine's safety production and operational management, and is also an important indicator of the mine's on-site management level. Therefore, continuously improving the standardized construction quality of ramp roads has significant long-term implications for reducing costs, ensuring safety, and enhancing economic efficiency. Attached Figure Description

[0024] The present invention will be further described below with reference to the accompanying drawings.

[0025] Figure 1 This is a schematic diagram of the slope road excavation operation of the present invention;

[0026] Figure 2 This is a schematic diagram of the standard platform for constructing a ramp road according to the present invention;

[0027] Figure 3 The schematic diagram of the operation method of the present invention is a turning around in the ramp;

[0028] Figure 4 The schematic diagram of the operation method of this invention is a U-turn outside the ramp;

[0029] Figure 5 This is a schematic diagram of the ramp indicator for the operation method of the present invention;

[0030] Figure 6 This is a schematic diagram of the on-site operation method of the present invention. Detailed Implementation

[0031] A method for efficient mining operations on inclined roads using electric shovels, characterized by the following steps:

[0032] The first step is to determine the standards for the ramp: Before starting ramp construction, the span and distance between the upper and lower ends of the ramp to be constructed must be observed to determine the required slope. The basic elements of a ramp include: ramp width, ramp depth, longitudinal slope, and ramp length. These are calculated based on the current climbing ability and safety distance of iron ore transport vehicles.

[0033] The second step is to rationally plan the blasting area (refer to blasting operation standards): The completion of a slope road often involves many factors, and the quality of the explosive material in the blast pile is one of the main factors affecting the progress of slope excavation. To ensure blasting quality, blasting personnel must strictly follow the requirements and prepare pre-loaded explosives, especially in areas with high moisture content, allowing sufficient settling time to ensure the explosives' effectiveness. The amount of explosive in the blast holes should be appropriately increased, and vibration-damping blasting should be used near the final slope. If the explosive material in the blast pile is too large, it will increase the excavation resistance of the electric shovel, seriously affecting the excavation progress. The parameters of the blast pile also have certain requirements, such as a length of no less than 175 meters and a width of no less than 40 meters. The entrance to the slope is the edge of the resistance line; if there is any collapse, it needs to be filled in promptly. Before construction, the blasting area must be carefully inspected to confirm whether there are large chunks or frozen soil clods on the top of the blasting area; if so, they must be dealt with immediately.

[0034] The third step involves mining methods and ore truck turning procedures: A reasonable mining method and correct equipment operation by the driver are crucial to the excavation progress, and the design of the ramp entrance is paramount. First, conditions must be created for the ore trucks to transport the ore. The equipment should be moved to the center of the road to expand the turning area for the ore trucks, ensuring the excavation area does not exceed the warning points placed by the foreman. If there is insufficient ore for loading, the excavator should be used to retract the ore from the turning area. Once the area has been sufficiently expanded, the equipment should be moved to the side where the cables are laid out for loading operations.

[0035] Step 4, the operation method for the ramp at night: From the perspective of the safety of ramp operation, there are potential safety hazards for drivers during the measurement process at night. Therefore, it is required to excavate the ramp in a flat mining mode at night, and the gradient shall be controlled by the daytime driver. This requires the daytime driver to measure the depth of the ramp every 10 meters of forward excavation during the mining process, that is, the vertical distance from the upper level to the lowest excavated point increases by 0.8 meters. During the excavation process, the driver shall cooperate with the inclinometer on the equipment to control the excavation depth, and the inclinometer of the equipment shall always be controlled between 4 and 5 degrees. The actual depth measurement and the angle control of the equipment's inclinometer complement each other. Standard calculation of the ramp (1) Ramp standard: The ramp has a length of 175M, a width of 26M, and a gradient of 8%. (2) Pavement evenness: There shall be no pits or bumps with a diameter of 50CM and a height or depth of more than 30CM, and no mud pumping phenomenon. (3) Turning arrangement: The cross slope of the turning area is maintained at 1.5%-2%. The inner side must have a pavement widening of 2.5M-3M, the superelevation is determined according to the pavement width and cross slope, and the inner side of the driving vehicles on the pavement of the turning area has a driving sight distance of no less than 50M. (4) Safety retaining wall: The safety retaining wall is uniformly designed according to the tire diameter requirement of the ore transport vehicle, that is, the cross section is an isosceles trapezoid, with a bottom width of no less than 5M, a top width of 1M, and a retaining wall height of 1.5M. In the formula: h — bench height, 14m i — gradient, from Tan<i=8%, it is deduced that L=h / i=14 / 0.08=175M, and the horizontal distance is 175M. Note: (1) According to the Pythagorean theorem: a 2 +b 2 =c 2 it is concluded that the length of the ramp is 175.56 meters (the difference from the ramp length is negligible). (2) Conversion between gradient and angle: (Tan<i=14m / 175m)=4 degrees and 34 minutes (the 8% gradient is converted to an angle of 4 degrees and 34 minutes). The entrance of the ramp is the edge of the burden, and if there is collapse, it needs to be filled and leveled in time. No other equipment shall operate in the same direction under the excavation area to prevent sudden sliding of large blocks from causing injury to the equipment and personnel below. Construction personnel shall set out points on the muck pile for the width and length of the road repair to serve as a warning.

[0036] In the second step, the forward thrust of the blasted material source must be longer and wider than the ramp. If the remaining material source is also excavated using road-building equipment, it will inevitably affect the project progress. To expedite the project, another excavator is needed to work on the next level. To control the length and width of the ramp, technicians need to precisely place the excavation points. These points are particularly important; they should be placed 175 meters long and 40 meters wide above the material source. The excavator working on the next level will excavate the excess material according to the placed warning signs. It is important to note that the upper and lower equipment must cooperate and operate in opposite directions when working simultaneously. When the two machines have excavated to a point 5-8 meters from each other, the lower equipment must immediately move to a safe location, constantly observing the warning signs, and avoiding over-excavation to prevent landslides. The ore truck uses different turning methods to reverse at the initial and later stages of the slope. Based on the slope width (26 meters) and the turning radius of the 172-type ore truck, two turning methods are calculated to meet the needs of the ore truck: turning around outside the slope and turning around and testing inside the slope. When there is a 0.5-meter height difference between the slope and the next horizontal plane, the driver judges by the top of the 10-foot shovel's top wheel approaching the previous horizontal plane (the top wheel is 13.5 meters from the ground). It is necessary to adjust the digging depth of the electric shovel, starting from 5 degrees on the angle gauge and gradually adjusting towards 0 degrees.

[0037] The rapid construction of ramp roads has improved the transportation efficiency of ore trucks, reduced costs, and decreased the occurrence of accidents, laying the foundation for achieving optimal economic benefits and ensuring safe production in the mine. The method developed through mining the north side of the 1402-1388 level is based on previous experience with ramp road construction and is suitable for using a combination of WK-10B electric shovels and hydraulic shovels. All economic and technical indicators are superior to previous projects. The progress and difficulty of this ramp road construction are significantly improved compared to previous projects, and the slope and length of the ramp meet the standards. Considering the operating efficiency of the electric shovel, the current construction method allows for completion 20 shifts ahead of schedule compared to previous road construction methods, and the ramp can be put into production 10 days earlier, shortening the preparation period for the new level. Completing the project 10 days ahead of schedule allows for an additional 10 days' worth of production (20 shifts). At a shift efficiency of 7890 tons / shift, this translates to an additional 7890 × 20 = 157,800 tons of ore. Considering transportation costs, the main expenses are tires and fuel consumption. These two factors combined account for approximately 60% of the total cost of open-pit mining. Their levels directly impact the overall production cost of the open-pit mine and its economic benefits. Standard sloping roads reduce fuel consumption for ore trucks and ensure their safe operation. Regarding auxiliary equipment, eliminating the previous need for pre-loading and hauling significantly reduces the operating costs of auxiliary equipment.

[0038] The construction of ramp roads is a crucial component of the entire open-pit mine production system. The level of standardized construction quality of ramp roads directly impacts the mine's safety production and operational management, and is also an important indicator of the mine's on-site management level. Therefore, continuously improving the standardized construction quality of ramp roads has significant long-term implications for reducing costs, ensuring safety, and enhancing economic efficiency.

[0039] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A method for efficient mining operations on inclined roads using electric shovels, characterized in that, Includes the following steps: The first step is to determine the standards for the sloping road: Before starting to build a slope, the span and distance between the upper and lower ends of the slope to be built must be observed to determine the size of the slope. The basic elements of a slope include: slope width, slope depth, longitudinal slope and slope length, which are calculated based on the current climbing ability and safety distance of iron ore transport vehicles. The second step is to rationally plan the hot zones: To ensure blasting quality, blasting personnel must strictly adhere to requirements. Pre-loading of explosives is essential, especially in areas with high moisture content, where sufficient settling time is crucial to maximize explosive effectiveness. The amount of explosive in each blast hole should be appropriately increased, and shock-absorbing blasting should be used near the final slope. The length of the blast pile must be no less than 175 meters, and the width no less than 40 meters. The entrance to the ramp is the edge of the resistance line; any collapse must be promptly filled in. Before construction, the blasting area must be carefully inspected to ensure the top of the blasting area is free of large chunks and frozen soil; if any are found, immediate action must be taken. The third step involves mining methods and the turning mechanism of ore transport vehicles: First, conditions must be created for the transport of ore by moving the equipment to the center of the road and expanding the reversing area for the ore trucks. The excavation area must not exceed the warning points placed by the construction worker. If there is not enough cargo to load, the excavator must be used to remove the cargo from the reversing position. After the area has been fully expanded, the equipment should be moved to the side where the cables are laid for loading operations. Step 4: Nighttime operation methods on sloping roads: From a safety perspective, there are potential safety hazards for drivers during nighttime measurements. Therefore, it is required that the slope be excavated at night using a flat excavation method, with the slope controlled by the driver during the day. This necessitates that the driver measure the slope depth every 10 meters during daytime excavation, with the vertical distance from the top horizontal point to the lowest point increasing by 0.8 meters. The driver must use the angle gauge on the equipment to control the excavation depth during the excavation process, and the angle gauge should always be kept between 4 and 5 degrees. The actual depth measurement and the angle control by the equipment angle gauge complement each other.

2. The efficient mining method for inclined roads using electric shovels according to claim 1, characterized in that, In the first step, (1) the standard of the sloping road: the length of the sloping road is 175m, the width is 26m, and the slope is 8%; (2) the road surface flatness: there shall be no potholes with a diameter of 50cm or more and an indentation of 30cm or more, and no mud pumping or mud splashing; (3) the setting of the turning area: the cross slope of the turning area shall be maintained at 1.5%-2%, and the inner side shall have a road surface widening of 2.5m-3m. The superelevation shall be determined according to the road width and cross slope. The inner side of the road surface of the turning area shall have a driving sight distance of not less than 50m; (4) the safety retaining wall: the safety retaining wall shall be designed according to the tire diameter requirements of the mining vehicle, that is, the cross section is an isosceles trapezoid, the bottom width is not less than 5m, the top width is 1m, and the wall height is 1.5m; the horizontal distance is 175-176m.

3. The efficient mining method for inclined roads using electric shovels according to claim 1, characterized in that, In the second step, no other equipment should be operating in the same direction below the excavation area to prevent large blocks from suddenly sliding down and causing damage to the equipment and personnel below; construction workers should mark the width and length of the road to be built on the blast pile as a warning.

4. The efficient mining method for inclined roads using electric shovels according to claim 1, characterized in that, In the second step, the forward thrust of the blasted material source should be longer and wider than the ramp. If the remaining material source is also excavated using road construction equipment, it will inevitably affect the project progress. To speed up the project, another excavator is needed to work on the next level. To control the length and width of the ramp, technicians need to accurately place the excavation points. The placement of these points is particularly important. The points should be placed 175 meters long and 40 meters wide above the material source. The excavator working on the next level should excavate the excess material source according to the placed warning signs. It is important to note that the upper and lower equipment should cooperate with each other and work in opposite directions when working simultaneously. When the two equipment have excavated to an intersection of 5-8 meters, the equipment working below should promptly move to a safe position, constantly observe the warning signs, and avoid over-excavation to prevent landslides.

5. The efficient mining method for inclined roads using electric shovels according to claim 1, characterized in that, In the third step, the ore truck reverses using different turning methods at the beginning and middle and later stages of the slope. Based on the width of the slope and the turning radius of the 172 type ore truck, two turning methods are calculated to meet the needs of the ore truck: turning outside the slope and turning back inside the slope.

6. The efficient mining method for inclined roads using electric shovels according to claim 1, characterized in that, In the fourth step, when the slope is 0.5 meters away from the next horizontal plane, the driver judges by the top of the 10-foot shovel's top wheel approaching the previous horizontal plane. The top wheel is 13.5 meters away from the ground, and the digging depth of the electric shovel needs to be adjusted, starting from 5 degrees on the angle gauge and gradually adjusting towards 0 degrees.

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